Published online by Cambridge University Press: 04 January 2023
A short squeeze occurs if borrowed shares are recalled and the short seller is unable to find another source of shares. This forces the short seller to terminate a position early. For most stocks, the probability of a short squeeze is very low. Short squeezes, however, are not unusual for the hardest to borrow stocks. For these stocks, trading costs from squeezes are high and have a significant impact on the returns to short selling. For hard-to-borrow stocks, short sellers also miss out on significant abnormal returns because squeezes force them to close positions.
I am grateful to Hendrik Bessembinder (the editor), Joseph Engelberg (the referee), Ben Golez, Adam Reed, Avanidhar Subrahmanyam, Kumar Venkataraman, and seminar participants at the University of Notre Dame and the 2021 Florida State University Suntrust Beach Conference for helpful comments and suggestions and to Nathan Kholodenko for clarifying how short-selling variables are calculated by IHS Markit and for explaining institutional details of the stock lending market.